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NetLogo User Community Models

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by Evgeniy Patarakin (Submitted: 04/05/2011)

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Wikis are collaborative platforms for text creation. The original idea of hypertext, expressed by V.Bush, D.Engelbart and T.Bernes-Lee treated it as an extension not only of individual, but of collective capabilities. Wiki is a simple and radical instance of a collective hypertext, in which every community member can create and edit pages. Wikis are often referred to as tools for conducting collective activities. Wiki philosophy implies aiming the efforts of the whole group at creating a collective final product. A group of wiki users can elaborate a collective hypertext and not bother with maintaining links. Usually wikis are regarded as encyclopedias consisting of multiple interconnected entries or as a multi-agent network community. In this paper we refer to wikis as ecological systems which consist of multiple human and programmed agents, following certain rules and an environment of various objects, pages, templates and categories and links between them. All the elements of the wiki environments can be reused. The transclusion mechanism allows to use wikis as building blocks and construct complicated metabolic chains. Well known wiki examples are collections of entries created by the community and are indicative examples of ecological systems.


The model is based on three simple rules.
• The system contains only participants, pages and links.
• Participants can act over pages.
• All participants’ actions over the pages are recorded and used for the wiki system dynamics analysis.

Participants possess the following properties:
Age and status. Every participant has an age which is equal to 0 at his birth. At every cycle it increases by 1. He also possesses a “retirement” property on achieving which he leaves the system. When the age overpasses retirement, the participant ceases his actions. Every participant has a “status” which can be a user or an administrator. Administrators are painted white, they are larger, they never retire. Every participant has active? property. If a participant becomes older than the retirement age his active? status is switched to “false”.
Each participant can be connected to several lists:
impact – is a list which allows to find all pages edited by the participant.
readlist – is a list of pages read by the author.
votelist – is a list of pages for which the participant voted. Each participant can vote for a page only once. He can not vote for the pages which he has created himself.
Each participant has the following abilities:
• The ability to read pages. After the agent has read a page, it can link it to other pages, grow other pages from it and link it to other pages.
• The ability to create new pages. A participant creates his page, writes its ID number to his impact list and writes his ID to the page history. The new page receives a directed pagelink from the parent page.
• The ability to edit existing pages. A participant changes the “size” property of the page, adds its ID to his impact list and adds his ID to the history of the page edits.
• The ability to link pages. A participant creates a directed link between pages. One page becomes a parent, the other becomes an offspring.
• The ability to evaluate pages. A participant can evaluate pages, created by other participants and read by him.
Pages can have their own properties inside the system.
• History is a list of edits and participants who edited the page.
• Page links to the page and from the page.
Two types of directed links are maintained in the system:
• Pagelinks are links between pages, established at the creation of a page and as a result of linking two existing pages.
• Uplinks are pages between participants and pages. These links are created as a result of the system analysis. For creating those links “Collaboration” button is used. Uplinks may vary in thickness, which depends on the contribution of the participant to editing the page.


The setup button clears off all the content from the system and creates the initial page, protected from erasing. It is a size 2 white page. The On/Off switch controls the OpenWiki variable.
The system can be closed. In this case all the content is published by the administrator.
The system can be open. In this case new users can come and create new pages.
Sliders control abilities of the participants.
• reading is the ability to read pages
• writing is the ability to write pages
• linking is the ability to link pages
• editing is the ability to edit pages
• voting is the ability to vote for and against pages
• erasing - is the ability to delete pages
• protecting - is the ability to protect


Collaboration button creates a graph, connecting participants and pages which they edited. Links between pages are hidden. The thickness of the page depends on the number of edits that the participant made


Set On/Off OpenWiki to Off. Run it with a small number of administrators (like 5) and watch the plot and hystograms. Then Set On/Off OpenWiki to On and watch the plot.


More sliders and hystograms can be added for wiki-system analysis.


Both users and pages are turtles. Pagelinks and uplinks are links.
Lists are used heavily in this model. Each page maintains a list of its editors. Each users maintains a list of pages he has edit. nodes.


See other models in the Networks section of the Models Library, such as Preferential Attachment.


This model is based on experience

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